Engine lubricant containing polyether compounds

ABSTRACT

The present invention relates to lubricant compositions for scooter engines and methods for reducing static friction between ferrous and non-ferrous surfaces as may be found in a wet clutch. The lubricant compositions contain polyether compounds in combination with one or more ash-free friction modifiers.

BACKGROUND OF THE INVENTION

The present invention relates to lubricant compositions primarily, butnot exclusively intended for 4-stroke, typically air-cooled scooter andmotorcycle engines, that demonstrate reduced static clutch frictionbetween ferrous and non-ferrous surfaces, such as conventionally foundin a motorcycle wet clutch.

Conventionally, at least two approaches for reducing static clutchfriction are known. First, lubricants may be formulated to have desiredclutch friction properties that meet desired specifications. Second,lubricants may be modified with a booster package or concentrate ofadditives intended to adjust the clutch friction performance of thelubricant to the desired specification. Amongst additives commonlyemployed as booster additives to reduce clutch friction performance, aremolybdenum compounds, such as molybdenum dithiocarbamate compounds.These compounds can be costly. Other additives used in boostinglubricants to reduce static clutch friction, such as certain phenolcompounds, which are employed as solubilizers, are coming underincreasing regulatory pressure. Accordingly, there is a need forcost-effective and functional additive components that may be employedin lubricants, including in booster packages for lubricants that willeffectively reduce clutch friction, while not unduly harming otherperformance properties, such as fuel economy, cleanliness, dispersancy,wear and the like.

The disclosed technology, therefore, addresses the problem of providinglubricants and booster packages for lubricants that effectively reducethe static friction in a clutch having at least one ferrous and onenon-ferrous clutch plate. Further the disclosed technology solves theproblem of providing lubricants and booster packages for lubricants thatboth effectively reduce static friction, while maintaining or improvingat least one of fuel economy, cleanliness and wear. This is accomplishedby the surprising discovery that certain polyethers and polyetheramines,in effective treat rates, reduce static friction between the ferrous andnon-ferrous surfaces in a clutch having at least one ferrous and onenon-ferrous clutch plate. Moreover, a combination of polyethers and/orpolyetheramines and ashless friction modifiers, in effective treatrates, provides reduced static friction while synergistically preservingfuel economy.

SUMMARY OF THE INVENTION

The present invention provides a lubricant composition comprising (a) anoil of lubricating viscosity, (b) a polyether compound, (c) anover-based detergent, (d) an ash-free friction modifier, (e) adispersant, and (f) optionally, an antioxidant.

According to one embodiment, the polyether compound may comprise apolyetheramine.

According to still another embodiment, the ash-free friction modifiermay be derived from an alpha-hydroxy carboxylic acid, such as aderivative of tartaric acid, citric acid, malic acid, lactic acid,glycolic acid, oligomers of said acids, or combinations thereof.

According to still another embodiment, the ash-free friction modifiermay be an imide, ester, or amide of tartaric acid, and in oneembodiment, may be a tartaric acid imide.

According to another embodiment the over-based detergent may comprise ametal containing detergent and wherein the metal is selected from thegroup consisting of sodium, magnesium and calcium.

According to another embodiment, the over-based detergent may beselected from the group consisting of sulfonates, phenates, salicylates,salixarates and mixtures thereof.

According to another embodiment, the detergent may comprise a calciumsulfonate detergent.

According to one embodiment, the lubricating composition the over-baseddetergent may be free or substantially free of phenates.

According to one embodiment, the lubricating composition may be free orsubstantially free of phenolic compounds, an in one embodiment, may befree or substantially free of alkyl phenolic compounds.

In one embodiment, the lubricating composition may comprise a molybdenumcontaining compound, and in an alternative embodiment, may be free orsubstantially free of a molybdenum containing compound.

In still another embodiment, a lubricating composition may comprise (a)a major amount of an oil of lubricating viscosity, (b) 0.05 to 3.0 wt. %(or 0.1 to 2.0 wt. % or 0.1 to 1.0 wt. % or 0.2 to 0.8 wt. %) of apolyether compound, (c) 0.05 to 3.0 wt. % (or 0.1 to 2.0 wt. % or 0.1 to1.0 wt. % or 0.2 to 0.8 wt. %) of an over-based detergent, (d) 0.05 to2.0 wt. % (or 0.1 to 1.0 wt. % or 0.1 to 0.8 wt. % or 0.2 to 0.8 wt. %)of an ash-free friction modifier, and (e) 0.1 wt. % to 20 wt. %, (or 1.0wt. % to 15 wt. %, or 1.5 wt. % to 10 wt. %, or 2 wt. % to 6 wt. %) of adispersant.

In further embodiments, the present invention provides methods oflubricating a wet clutch by supplying to the wet clutch a lubricatingcomposition as taught herein.

In another embodiment, the present invention provides methods ofreducing static friction between a ferrous and non-ferrous surface in awet clutch, wherein the wet clutch comprises at least one clutch platehaving a non-ferrous surface and at least one clutch plate having aferrous surface, the methods comprising supplying between the ferrousand non-ferrous clutch plate surfaces a lubricating composition astaught herein.

In another embodiment, the present invention provides methods oflubricating an engine comprising supplying to an engine a lubricatingcomposition as taught herein.

In some embodiments, the engine may be a 4-stroke engine, and usefullyan air-cooled engine, and typically an engine providing less than about150, or 125 or 100 or 85 horsepower.

In one embodiment, the method of lubricating the engine comprisessupplying a lubricant composition that does not lubricate a wet clutch.

According to another embodiment, there is provided an additiveconcentrate for top treating a lubricating composition, comprising (a) 2to 35 wt. % (or 5 to 30 wt. % or 10 to 25 wt. % or 10 to 20 wt. %) of apolyether compound, (b) 2 to 25 wt. % (or 3 to 20 wt. % or 5 to 20 wt. %or 7 to 15 wt. %) of an ash-free friction modifier, and (c) 10 to 80 wt.% (or 10 to 75 wt. % or 30 to 75 wt. % or 40 wt. % to 70 wt. %) of ametal containing, over-based detergent.

According to yet another embodiment, there is provided a lubricantcomposition comprising (a) a major amount of an oil of lubricatingviscosity, and (b) 0.5 to 5.0 wt. % (or 0.5 to 3.0 wt. % or 0.5 to 1.5wt. %) of an additive concentrate provided herein.

The disclosed technology further provides lubricating compositions thatprovide reduced static friction while maintaining fuel economy.

In one embodiment, the lubricant has a static friction characteristicindex (SFI) according to JASO T903:2011 MB specifications of less than1.25 and in another embodiment, between 0.5 and 1.25.

DETAILED DESCRIPTION OF THE INVENTION

Various features and embodiments will be described below by way ofnon-limiting illustration.

The present invention provides, in one embodiment, a lubricantcomposition comprising (a) an oil of lubricating viscosity, (b) apolyether compound, (c) an over-based detergent, (d) an ash-freefriction modifier, (e) a dispersant, and (f) optionally, an antioxidant.

Oil of Lubricating Viscosity

The lubricating composition comprises an oil of lubricating viscosity.Such oils include natural and synthetic oils, oil derived fromhydrocracking, hydrogenation, and hydrofinishing, unrefined, refined andre-refined oils and mixtures thereof.

Unrefined oils are those obtained directly from a natural or syntheticsource generally without (or with little) further purificationtreatment. Refined oils are similar to the unrefined oils except theyhave been further treated in one or more purification steps to improveone or more properties. Purification techniques are known in the art andinclude solvent extraction, secondary distillation, acid or baseextraction, filtration, percolation and the like. Re-refined oils arealso known as reclaimed or reprocessed oils, and are obtained byprocesses similar to those used to obtain refined oils and often areadditionally processed by techniques directed to removal of spentadditives and oil breakdown products.

Natural oils useful in making the inventive lubricants include animaloils, vegetable oils (e.g., castor oil,), mineral lubricating oils suchas liquid petroleum oils and solvent-treated or acid-treated minerallubricating oils of the paraffinic, naphthenic or mixedparaffinic-naphthenic types and oils derived from coal or shale ormixtures thereof.

Synthetic lubricating oils are useful and include hydrocarbon oils suchas polymerized and interpolymerized olefins (e.g., polybutylenes,polypropylenes, propylene-isobutylene copolymers); poly(1-hexenes),poly(1-octenes), poly(1-decenes), and mixtures thereof; alkyl-benzenes(e.g., dodecylbenzenes, tetradecylbenzenes, dinonylbenzenes,di-(2-ethylhexyl)-benzenes); polyphenyls (e.g., biphenyls, terphenyls,alkylated polyphenyls); diphenyl alkanes, alkylated diphenyl alkanes,alkylated diphenyl ethers and alkylated diphenyl sulfides and thederivatives, analogs and homologs thereof or mixtures thereof.

Other synthetic lubricating oils include polyol esters (such asPriolube®3970), diesters, liquid esters of phosphorus-containing acids(e.g., tricresyl phosphate, trioctyl phosphate, and the diethyl ester ofdecane phosphonic acid), or polymeric tetrahydrofurans. Synthetic oilsmay be produced by Fischer-Tropsch reactions and typically may behydroisomerized Fischer-Tropsch hydrocarbons or waxes. In one embodimentoils may be prepared by a Fischer-Tropsch gas-to-liquid syntheticprocedure as well as other gas-to-liquid oils.

Oils of lubricating viscosity may also be defined as specified in theAmerican Petroleum Institute (API) Base Oil InterchangeabilityGuidelines. The five base oil groups are as follows: Group I (sulfurcontent >0.03 wt. %, and/or <90 wt. % saturates, viscosity index80-120); Group II (sulfur content <0.03 wt. %, and >90 wt. % saturates,viscosity index 80-120); Group III (sulfur content <0.03 wt. %, and >90wt. % saturates, viscosity index >120); Group IV (all polyalphaolefins(PAOs)); and Group V (all others not included in Groups I, II, III, orIV). The oil of lubricating viscosity may also be an API Group II+ baseoil, which term refers to a Group II base oil having a viscosity indexgreater than or equal to 110 and less than 120, as described in SAEpublication “Design Practice: Passenger Car Automatic Transmissions,”,4th Edition, AE-29, 2012, page 12-9, as well as in U.S. Pat. No.8,216,448, column 1, line 57.

The oil of lubricating viscosity may be an API Group IV oil, or mixturesthereof, i.e., a polyalphaolefin. The polyalphaolefin may be prepared bymetallocene catalyzed processes or from a non-metallocene process.

The oil of lubricating viscosity comprises an API Group I, Group II,Group III, Group IV, Group V oil or mixtures thereof. Often the oil oflubricating viscosity is an API Group I, Group II, Group II+, Group III,Group IV oil or mixtures thereof. Alternatively, the oil of lubricatingviscosity is often an API Group II, Group II+, Group III or Group IV oilor mixtures thereof. Alternatively, the oil of lubricating viscosity isoften an API Group II, Group II+, Group III oil or mixtures thereof.

The amount of the oil of lubricating viscosity present is typically thebalance remaining after subtracting from 100 wt. % the sum of the amountof the additive as described herein above, and the other performanceadditives. Typically, the major part of the fully formulated lubricatingcompositions disclosed herein, that is, greater than 50 wt. % of thefully formulated lubricating compositions, will consist of one or moreoils of lubricating viscosity. Typically, the lubricating composition ofthe disclosed technology comprises at least 60 wt. %, or at least 70 wt.%, or at least 80 wt. % or at least 90 wt. % of an oil of lubricatingviscosity.

The lubricating composition may be in the form of a concentrate and/or afully formulated lubricant. If the lubricating composition of theinvention is in the form of a concentrate (which may be combined withadditional oil to form, in whole or in part, a finished lubricant), theratio of the of components of the invention to the oil of lubricatingviscosity and/or to diluent oil include the ranges of 1:99 to 99:1 byweight, or 80:20 to 10:90 by weight.

In certain embodiments, the lubricating composition may containsynthetic ester base fluids. Synthetic esters may have a kinematicviscosity measured at 100 C of 2.5 mm²/s to 30 mm²/s. In one embodiment,the lubricating composition comprises less than 50 wt. % of a syntheticester base fluid with a kinematic viscosity at 100 C of at least 5.5mm²/s, or at least 6 mm²/s, or at least 8 mm²/s.

Synthetic esters of the present invention may comprise esters of adicarboxylic acids (e.g., phthalic acid, succinic acid, alkyl succinicacids and alkenyl succinic acids, maleic acid, azelaic acid, subericacid, sebacic acid, fumaric acid, adipic acid, linoleic acid dimer,malonic acid, alkyl malonic acids, and alkenyl malonic acids) with anyof variety of alcohols (e.g., butyl alcohol, hexyl alcohol, dodecylalcohol, 2-ethylhexyl alcohol, ethylene glycol, diethylene glycolmonoether, and propylene glycol). Specific examples of these estersinclude dibutyl adipate, di(2-ethylhexyl) sebacate, di-n-hexyl fumarate,dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctylphthalate, didecyl phthalate, dieicosyl sebacate, the 2-ethylhexyldiester of linoleic acid dimer, and the complex ester formed by reactingone mole of sebacic acid with two moles of tetraethylene glycol and twomoles of 2-ethylhexanoic acid.

Esters useful as synthetic oils also include those made from C5 to C12monocarboxylic acids and polyols and polyol ethers such as neopentylglycol, trimethylolpropane, pentaerythritol, dipentaerythritol, andtripentaerythritol. Esters can also be monoesters, such as are availableunder the trade name Priolube 1976™ (C18-alkyl-COO—C20 alkyl).

Synthetic ester base oils may be present in the lubricating compositionof the invention in an amount less than 50 wt. % of the composition, orless than 40 wt. %, or less than 35 wt. %, or less than 28 wt. %, orless than 21 wt. %, or less than 17 wt. %, or less than 10 wt. %, orless than 5 wt. % of the composition. In one embodiment, the lubricatingcomposition of the invention is free of, or substantially free of, asynthetic ester base fluid having a kinematic viscosity of at least 5.5mm²/s at 100 C.

Polyether Compound

In the present technology, the lubricating composition comprises an oilof lubricating viscosity and a polyether compound. In one embodiment,the polyether compound may comprise a polyether amine or a blend ofpolyethers and polyetheramines.

The polyether compounds of the present invention may be represented bythe Formula 1:

RO[CH₂CH(R¹)O]_(n)A   Formula 1

where R is a hydrogen or a linear, branched, or cyclic hydrocarbyl groupof 1 to 32 (or 1 to 26 or 2 to 26 or 4 to 24 or 8 to 20 or 10 to 20 or12 to 18) carbon atoms,

R¹ is selected from the group consisting of hydrogen, hydrocarbyl groupsof 1 to 6 (or 1 to 4 or 1 to 2 or 1 or 2) carbon atoms, and mixturesthereof,

n is a number from 2 to about 50 (or 12 to 36 or 18 to 30 or 2 to 20),and

A is selected from the group consisting of hydrogen, R¹, —RNR²R², C═OR⁸and —NR³R³, where

each R² is independently hydrogen or a hydrocarbyl group of 1 to 24 (or2 to 24 or 4 to 20 or 8 to 20 or 12 to 18 or 2 to 12) carbon atoms,

each R³ is independently hydrogen, a hydrocarbyl group of 1 to 24 (or 2to 24 or 4 to 20 or 8 to 20 or 12 to 18 or 2 to 12) carbon atoms, or—[R⁴N(R⁵)]_(p)R⁶

R⁴ is C₂-C₁₀ alkylene,

R⁵ and R⁶ are independently hydrogen or a hydrocarbyl group of 1 to 6(or 1 to 4 or 1 to 2 or 2 to 4),

R⁷ and R⁸ are independently hydrogen or a hydrocarbyl group of 1 to 6(or 1 to 4 or 1 to 2 or 2 to 4 or 3) carbon atoms, and

p is a number from 1-7.

Useful polyetheramines can be prepared by condensing hydric compoundsuch as an alcohol or alkylphenol with an alkylene oxide, mixture ofalkylene oxides or with several alkylene oxides in sequential fashion ina 1:2-50 mole ratio of hydric compound to alkylene oxide, typicallyethylene oxide, to form a polyether. U.S. Pat. No. 5,094,667 providesreaction conditions for preparing a polyether, the disclosure of whichis incorporated herein by reference.

The alcohols can be linear or branched from 1 to 32 carbon atoms, orfrom 1 to 26 or 2 to 26 or 4 to 24 or 8 to 20 or 10 to 20 or 12 to 18carbon atoms. The alkyl group of the alkylphenols may have a similarrange of carbon atoms as the alcohols.

The alkylene oxides are preferably ethylene oxide, propylene oxide orbutylene oxide.

The number of alkylene oxide units in the polyether may be from 2 to 50,or 12 to 36 or 18 to 30 or 2 to 20.

In one particularly useful embodiment, the polyether compound may be apolyetheramine. The polyetheramines of the present invention may be asrepresented by Formula 1:

where R is a hydrogen or hydrocarbyl group of 1 to 32 (or 1 to 26 or 2to 26 or 4 to 24 or 8 to 20 or 10 to 20 or 12 to 18) carbon atoms,

R¹ is selected from the group consisting of hydrogen, hydrocarbyl groupsof 1 to 6 (or 1 to 4 or 1 to 2 or 1 or 2) carbon atoms, and mixturesthereof,

n is a number from 2 to about 50, and

A is selected from the group consisting of —R⁷NR²R² and —NR³R³,preferably —R⁷NR²R², where

each R² is independently hydrogen or a hydrocarbyl group of 1 to 24 (or2 to 24 or 4 to 20 or 8 to 20 or 12 to 18 or 2 to 12) carbon atoms,

each R³ is independently hydrogen, a hydrocarbyl group of 1 to 24 (or 2to 24 or 4 to 20 or 8 to 20 or 12 to 18 or 2 to 12) carbon atoms, or—[R⁴N(R⁵)]_(p)R⁶

where R⁴ is C₂-C₁₀ alkylene,

R⁵ and R⁶ are independently hydrogen or a hydrocarbyl group of 1 to 6(or 1 to 4 or 1 to 2 or 2 to 4),

R⁷ and R⁸ are independently hydrogen or a hydrocarbyl group of 1 to 6(or 1 to 4 or 1 to 2 or 2 to 4 or 3) carbon atoms, and

p is a number from 1-7.

Useful polyetheramines can be prepared by converting a polyetheramine,as described above, by amination with ammonia, an amine or a polyamineto form a polyetheramine of the type where A is —NR³R³. Published PatentApplication EP310875 provides reaction conditions for the aminationreaction, the disclosure of which is incorporated herein by reference.Alternately, the polyether intermediate can also be converted to apolyetheramine of the type where A is —R⁷NR²R² by reaction withacrylonitrile followed by hydrogenation. U.S. Pat. No. 5,094,667provides reaction conditions for the cyanoethylation and subsequenthydrogenation, the disclosure of which is incorporated herein byreference.

Polyetheramines according to Formula 1 where A is —R⁷NH₂ are useful.Commercial examples of useful polyetheramines are the Techron® rangefrom Chevron and the Jeffamine® range from Huntsman.

Where the polyether compound is part of a fully formulated lubricantcomposition, it may be present in an amount of about 0.05 to about 3.0wt. % (or about 0.1 to about 2.0 wt. % or about 0.1 to about 1.0 wt. %or about 0.2 to about 0.8 wt. %, with respect to the lubricatingcomposition. In another embodiment, however, the polyether compound maybe a component of an additive concentrate comprising the polyethercompound, an ash-free friction modifier and optionally, a detergent. Inthe additive concentrate, the polyether compound may be present (on anoil free basis) at about 2 to about 35 wt. % or about 5 to about 30 wt.% or about 10 to about 25 wt. % or about 10 to about 20 wt. %, withrespect to the additive concentrate.

Ash-Free Friction Modifier

The lubricant composition will also include at least one ash-freefriction modifier. The friction modifier is a non-metal containingadditive. A non-metal containing additive may also be referred to as anashless (or ash-free) additive, since it will typically not produce anysulfated ash when subjected to the conditions of ASTM D 874. An additiveis referred to as “non-metal containing” if it does not contribute metalcontent to the lubricant composition.

In certain embodiments, the friction modifier may be chosen from longchain fatty acid derivatives of amines, long chain fatty esters, orderivatives of long chain fatty epoxides; fatty imidazolines; aminesalts of alkylphosphoric acids; and fatty esters, amides and/or imidesof various hydroxy-carboxylic acids, such as tartaric acid, citric acid,malic acid, lactic acid, glycolic acid, and mandelic acid.

As used herein the term “fatty alkyl” or “fatty” in relation to frictionmodifiers means a carbon chain having 8 to 30 carbon atoms, typically astraight carbon chain.

In one embodiment, ash-free friction modifier may comprise an amide,ester or imide derivative of a hydroxycarboxylic acid. Such materialsand their syntheses are known from, for instance, PCT Publn. No. WO2006/044411 and US Publn. No. 2009/067091. They have been employed inlubricants for their properties as thermal or oxidative stability,deposit control, and friction control.

Examples of suitable hydroxy-carboxylic acids include citric acid,tartaric acid, lactic acid, malic acid, glycolic acid, hydroxy-propionicacid, hydroxyglutaric acid, and mixtures thereof. Oligomers of suchacids may also be employed (e.g., the self-condensate of glycolic acidby ester formation). In one embodiment, an amide, ester or imidederivative of a hydroxy-carboxylic acid may be derived from tartaricacid, citric acid, hydroxy-succinic acid, dihydroxy mono-acids,mono-hydroxy diacids, or mixtures thereof. In one embodiment, the amide,ester or imide derivative of a hydroxy-carboxylic acid includes aderivative (or compound derived from) tartaric acid or citric acid, or,in another embodiment, from tartaric acid.

In one embodiment the amide, ester or imide derivative of ahydroxy-carboxylic acid may be represented by Formula 2 (encompassing,2a or 2b):

wherein n′ is 0 to 10 for Formula 2b, and 1 to 10 for Formula 2a;

p is 1 to 5;

Y and Y′ are independently —O—, >NH, >NR3, or an imide group formed bytaking together both Y and Y′ groups in 2b or two Y groups in 1a andforming a R¹—N<group between two >C═O groups;

X is independently —CH₂—, >CHR⁴, >CR⁴R⁵, >CHOR⁶, >C(OH)CO₂R⁶,>C(CO₂R⁶)₂, —CH₃, —CH₂R⁴ or CHR₄R⁵, —CH₂OR⁶, —CH(CO₂R⁶)₂, ≡C—R⁶ (where ≡refers to three valences, and may only apply to Formula 1), or mixturesthereof, to fulfill the valence of Formula 2a and/or 2b (the compound ofFormula 2a or 2b may have at least one X that is hydroxyl-containing(i.e., >CHOR⁶, wherein R⁶ is hydrogen);

R¹ and R² are independently hydrocarbyl groups, typically containing 1to 150, or 4 to 30, or 8 to 15 carbon atoms;

R³ is a hydrocarbyl group;

R⁴ and R⁵ are independently keto-containing groups (such as acylgroups), ester groups, hydrocarbyl groups, —OR⁶, —CO₂R⁶, or —OH(typically not more than one —OH when X is >CR⁴R⁵); and

R⁶ is independently hydrogen or a hydrocarbyl group, typicallycontaining 1 to 150, or 4 to 30, or 8 to 15 carbon atoms.

In one embodiment, the compound of Formula 2 contains an imide group,which may be formed by taking together the Y and Y′ groups and forming aR¹—N<group between two >C═O groups. In one embodiment the compound ofFormula (1) has m, n, X, and R¹, R² and R⁶ defined as follows: m is 0 or1, n is 1 to 2, X is >CHOR⁶, and R¹, R² and R⁶ are independentlyhydrocarbyl groups containing 4 to 30 carbon atoms. In one embodiment, Yand Y′ are both —O—In one embodiment, the compound of Formula 2 has m,n, X, Y, Y′ and R¹, R² and R⁶ defined as follows: m is 0 or 1, n is 1 to2, X is >CHOR⁶; Y and Y′ are both —O—, and R¹, R² and R⁶ areindependently hydrogen or hydrocarbyl groups containing 4 to 30 carbonatoms.

The di-esters, di-amides, ester-amide, ester-imide compounds of Formula2 may be prepared by reacting a dicarboxylic acid (such as tartaricacid), with an amine or alcohol, optionally in the presence of a knownesterification catalyst. In the case of ester-imide compounds, it isnecessary to have at least three carboxylic acid groups (such asprovided by citric acid). The amine or alcohol which is reactedtypically has sufficient carbon atoms to fulfill the requirements of R¹and/or R² as defined in Formula 2.

In one embodiment R¹ and R² are independently linear or branchedhydrocarbyl groups. In one embodiment they are branched; in another theyare linear; or some may be branched and some linear. The R¹ and R² maybe incorporated into Formula 2 by either an amine or an alcohol. Thealcohol includes both monohydric alcohol and polyhydric alcohol. Thecarbon atoms of the alcohol may be linear chains, branched chains, ormixtures thereof.

Examples of suitable alcohols include 2-ethylhexanol, isotridecanol,Guerbet alcohols, methanol, ethanol, propanol, butanol, pentanol,hexanol, heptanol, Ctanol, nonanol, decanol, undecanol, dodecanol,tridecanol, tetradecanol, pentadecanol, hexadecanol, heptadecanol,Ctadecanol, nonadecanol, eicosanol, ethylene glycol, propylene glycol,1,3-butylene glycol, 2,3-butylene glycol, 1,5-pentane diol, 1,6-hexanediol, glycerol, sorbitol, pentaerythritol, trimethylolpropane, starch,glucose, sucrose, methylglucoside, or mixtures thereof. In oneembodiment, a polyhydric alcohol is used in a mixture along with amonohydric alcohol; in such a combination the monohydric alcohol mayconstitute at least 60 or at least 90 mole % of the mixture.

If the acid employed is tartaric acid, it may be a commerciallyavailable material, and it may exist in one or more isomeric forms suchas d-tartaric acid, 1-tartaric acid, d,l-tartaric acid or a racemicmixture of d-tartaric acid and 1-tartaric acid, or mesotartaric acid.

In certain embodiments, the hydroxycarboxylic acid derivative maycomprise a tartrimide such as a tartimide formed from a primary aminehaving 8 to 24 carbon atoms or 12 to 20 carbon atoms or 16 to 18 carbonatoms or mixtures thereof. In one embodiment, the tartrimide is oleyltartrimide. In other embodiments, the hydroxycarboxylic acid derivativemay comprise a tartrate ester such as a diester of tartaric acid and oneor more alcohols having 8 to 24 carbon atoms or 8 to 18 carbon atoms or12 to 14 carbon atoms. In one embodiment, the tartrate is the ester frommixed C12-C14 alcohols.

The amount of the ash-free friction modifier in a lubricant may be 0.05to 3.0 wt. % or 0.05 to 2.0 wt. % (or 0.1 to 1.0 wt. % or 0.1 to 0.8 wt.% or 0.2 to 0.8 wt. %) with respect to the lubricant composition. Theash-free friction modifier may also be present in a concentrate asdescribed above, where it may be present (on an oil free basis) at 2 to25 wt. % or 3 to 20 wt. % or 5 to 20 wt. % or 7 to 10 wt. %) withrespect to the additive concentrate. In a concentrate, the amount ofmaterial may be two to twenty times the above concentration amounts.

Detergents

In one embodiment, the invention provides a lubricating compositionfurther comprising an over-based, metal-containing detergent. The metalof the metal-containing detergent may be zinc, sodium, calcium, barium,or magnesium. Typically, the metal of the metal-containing detergent maybe sodium, calcium, or magnesium.

The over-based, metal-containing detergent may be chosen fromsulfonates, non-sulfur containing phenates, sulfur containing phenates,salixarates, salicylates, and mixtures thereof, or borated equivalentsthereof. The over-based detergent may be borated with a borating agentsuch as boric acid.

The over-based, metal-containing detergent may also include “hybrid”detergents formed with mixed surfactant systems including phenate and/orsulfonate components, e.g., phenate/salicylates, sulfonate/phenates,sulfonate/salicylates, sulfonates/phenates/salicylates, as described;for example, in U.S. Pat. Nos. 6,429,178, 6,429,179, 6,153,565 and6,281,179. For example, a “hybrid sulfonate/phenate detergent isemployed, the “hybrid detergent would be considered equivalent toamounts of distinct phenate and sulfonate detergents introducing likeamounts of phenate and sulfonate soaps, respectively.

Typically, an over-based, metal-containing detergent may be a zinc,sodium, calcium or magnesium salt of a sulfonate, a phenate, sulfurcontaining phenate, salixarate or salicylate. Over-based sulfonates,salixarates, phenates and salicylates typically have a total base numberof 120 to 700 TBN.

Typically, the over-based, metal-containing detergent may be a calciumor magnesium an over-based detergent.

In another embodiment, the lubricating composition comprises a calciumsulfonate over-based detergent, which may have a TBN of 120 to 700. Theover-based sulfonate detergent may have a metal ratio of 12 to less than20, or 12 to 18, or 20 to 30, or 22 to 25.

Over-based sulfonates typically have a total base number of 120 to 700,or 250 to 600, or 300 to 500 (on an oil free basis). Over-baseddetergents are known in the art. The sulfonate detergent may be a linearor branched alkylbenzene sulfonate detergent having a metal ratio of atleast 8 as is described in paragraphs [0026] to [0037] of US Publn. No.2005/065045 (granted as U.S. Pat. No. 7,407,919). Linear alkyl benzenesmay have the benzene ring attached anywhere on the linear chain, usuallyat the 2, 3 or 4 position, or mixtures thereof. Linear alkylbenzenesulfonate detergent may be particularly useful for assisting inimproving fuel economy. In one embodiment, the alkylbenzene sulfonatedetergent may be a branched alkylbenzene sulfonate, a linearalkylbenzene sulfonate, or mixtures thereof. In one embodiment, thelubricating composition may be free of linear alkylbenzene sulfonatedetergent. In one embodiment, the sulfonate detergent may be a metalsalt of one or more oil-soluble alkyl toluene sulfonate compounds asdisclosed in paragraphs [0046] to [0053] of US Publn. No. 2008/0119378.The detergent, such as a branched alkylbenzenesulfonate detergent, maybe present in the lubricating composition at 0.1 to 3 wt. %, or 0.25 to1.5 wt. %, or 0.5 to 1.1 wt. %.

In one embodiment, the lubricating composition further comprises a“hybrid” detergent formed with mixed surfactant systems includingphenate and/or sulfonate components, e.g., phenate/salicylates,sulfonate/phenates, sulfonate/salicylates, orsulfonates/phenates/salicylates.

Detergents may be present in an amount of 0.05 to 3.0 wt. % (or 0.1 to2.0 wt. % or 0.1 to 1.0 wt. % or 0.2 to 0.8 wt. %) with respect to thefully formulated lubricant composition. The detergent may be present inthe additive concentrate in an amount (on an oil free basis) of 10 to 80wt. % (or 10 to 75 wt. % or 30 to 75 wt. % or 40 wt. % to 70 wt. %) withrespect to the additive concentrate. In some embodiments, it may beuseful to include the detergent to assist in solubilizing the ash-freefriction modifier. In other embodiments, it may be useful to omit thedetergent from the additive concentrate.

Other Performance Additives

A lubricating composition may be prepared by adding the product of theprocess described herein to an oil of lubricating viscosity, optionallyin the presence of other performance additives (as described hereinbelow).

The lubricating composition of the disclosed technology optionallycomprises other performance additives. The other performance additivesmay include at least one of a molybdenum compound, a metal deactivators,viscosity modifiers, detergents, friction modifiers, antiwear agents,corrosion inhibitors, dispersants, extreme pressure agents,antioxidants, foam inhibitors, demulsifiers, pour point depressants,seal swelling agents (different from those of the invention) andmixtures thereof. Typically, fully-formulated lubricating oil willcontain one or more of these performance additives.

The lubricant composition may also include molybdenum containingcompounds, such as molybdenum containing dithiocarbamate compounds andnitrogen-containing molybdenum compounds, such as those described inU.S. Pat. No. 6,329,327; and organomolybdenum compounds made from thereaction of a molybdenum source, fatty oil, and a diamine as describedin U.S. Pat. No. 6,914,037.

The molybdenum compound may be present in the lubricant composition at0.005 to 2 wt. % of the composition, or 0.01 to 1.3 wt. % of thecomposition, or even 0.02 to 1.0 wt. % of the composition. Themolybdenum compound may provide the lubricant composition with 0 to 1000ppm, or 5 to 1000 ppm, or 10 to 750 ppm 5 ppm to 300 ppm, or 20 ppm to250 ppm of molybdenum. In some embodiments, however, the lubricantcomposition will be free or substantially free of molybdenum compounds.

The lubricating composition in a further embodiment may comprise anantioxidant, wherein the antioxidant comprises a phenolic or an aminicantioxidant or mixtures thereof. The antioxidants include diarylamines,alkylated diarylamines, hindered phenols, or mixtures thereof. Whenpresent, the antioxidant may be present at 0.1 wt. % to 3 wt. %, or 0.5wt. % to 2.75 wt. %, or 1 wt. % to 2.5 wt. % of the lubricatingcomposition.

The diarylamine or alkylated diarylamine may be a phenyl-α-naphthylamine(PANA), an alkylated diphenylamine, or an alkylated phenylnapthylamine,or mixtures thereof. The alkylated diphenylamine may includedi-nonylated diphenylamine, nonyl diphenylamine, Ctyl diphenylamine,di-octylated diphenylamine, di-decylated diphenylamine, decyldiphenylamine and mixtures thereof. In one embodiment, the diphenylaminemay include nonyl diphenylamine, dinonyl diphenylamine, Ctyldiphenylamine, dioctyl diphenylamine, or mixtures thereof. In anotherembodiment the alkylated diphenylamine may include nonyl diphenylamine,or dinonyl diphenylamine. The alkylated diarylamine may include Ctyl,di-octyl, nonyl, di-nonyl, decyl or di-decyl phenylnapthylamines.

The hindered phenol antioxidant often contains a secondary butyl and/ora tertiary butyl group as a sterically hindering group. The phenol groupmay be further substituted with a hydrocarbyl group (typically linear orbranched alkyl) and/or a bridging group linking to a second aromaticgroup. Examples of suitable hindered phenol antioxidants include2,6-di-tert-butylphenol, 4-methyl-2,6-di-tert-butylphenol,4-ethyl-2,6-di-tert-butylphenol, 4 propyl-2,6-di-tert-butylphenol or4-butyl-2,6-di-tert-butylphenol, or 4-dodecyl-2,6-di-tert-butylphenol.In one embodiment, the hindered phenol antioxidant may be an ester andmay include, e.g., Irganox™ L-135 from Ciba. A more detailed descriptionof suitable ester-containing hindered phenol antioxidant chemistry isfound in U.S. Pat. No. 6,559,105.

The lubricating composition may in a further embodiment include adispersant, or mixtures thereof. The dispersant may be a succinimidedispersant, a Mannich dispersant, a succinamide dispersant, a polyolefinsuccinic acid ester, amide, or ester-amide, or mixtures thereof. In oneembodiment the dispersant may be present as a single dispersant. In oneembodiment, the dispersant may be present as a mixture of two or threedifferent dispersants, wherein at least one may be a succinimidedispersant.

The succinimide dispersant may be derived from an aliphatic polyamine,or mixtures thereof. The aliphatic polyamine may be aliphatic polyaminesuch as an ethylenepolyamine, a propylenepolyamine, a butylenepolyamine,or mixtures thereof. In one embodiment, the aliphatic polyamine may beethylenepolyamine. In one embodiment, the aliphatic polyamine may bechosen from ethylenediamine, diethylenetriamine, triethylenetetramine,tetraethylenepentamine, pentaethylene-hexamine, polyamine still bottoms,and mixtures thereof.

In one embodiment, the dispersant may be a polyolefin succinic acidester, amide, or ester-amide. For instance, a polyolefin succinic acidester may be a polyisobutylene succinic acid ester of pentaerythritol,or mixtures thereof. A polyolefin succinic acid ester-amide may be apolyisobutylene succinic acid reacted with an alcohol (such aspentaerythritol) and a polyamine as described above.

The dispersant may be an N-substituted long chain alkenyl succinimide.An example of an N-substituted long chain alkenyl succinimide ispolyisobutylene succinimide. Typically, the polyisobutylene from whichpolyisobutylene succinic anhydride is derived has a number averagemolecular weight of 350 to 5000, or 550 to 3000 or 750 to 2500 g/moleSuccinimide dispersants and their preparation are disclosed, forinstance in U.S. Pat. Nos. 3,172,892, 3,219,666, 3,316,177, 3,340,281,3,351,552, 3,381,022, 3,433,744, 3,444,170, 3,467,668, 3,501,405,3,542,680, 3,576,743, 3,632,511, 4,234,435, 6,165,235, 7,238,650, Re26,433 and EP Publication No. 0355895A.

The dispersants may also be post-treated by conventional methods by areaction with any of a variety of agents. Among these are boroncompounds (such as boric acid), urea, thiourea, dimercaptothiadiazoles,carbon disulfide, aldehydes, ketones, carboxylic acids such asterephthalic acid, hydrocarbon-substituted succinic anhydrides, maleicanhydride, nitriles, epoxides, and phosphorus compounds. In oneembodiment, the post-treated dispersant is borated. In one embodiment,the post-treated dispersant is reacted with dimercaptothiadiazoles. Inone embodiment the post-treated dispersant is reacted with phosphoric orphosphorous acid. In one embodiment, the post-treated dispersant isreacted with terephthalic acid and boric acid (as described in US Publn.No. 2009/0054278.

The dispersant may be present at 0.1 wt. % to 20 wt. %, (or 1.0 wt. % to15 wt. %, or 1.5 wt. % to 10 wt. %, or 2 wt. % to 6 wt. % or 1 to 3 wt.%) of the lubricating composition.

The succinimide dispersant may comprise a polyisobutylene succinimide,wherein the polyisobutylene from which polyisobutylene succinimide isderived has a number average molecular weight of 350 to 5000, or 750 to2500 g/mole.

Another class of additives that may perform as antiwear agents as wellas in other roles includes oil-soluble titanium compounds as disclosedin U.S. Pat. No. 7,727,943 and US Publn. No. 2006/0014651. Theoil-soluble titanium compounds may function as antiwear agents, frictionmodifiers, antioxidants, deposit control additives, or more than one ofthese functions. In one embodiment the oil soluble titanium compound isa titanium (IV) alkoxide. The titanium alkoxide is formed from amonohydric alcohol, a polyol or mixtures thereof. The monohydricalkoxides may have 2 to 16, or 3 to 10 carbon atoms. In one embodiment,the titanium alkoxide is titanium (IV) isopropoxide. In one embodiment,the titanium alkoxide is titanium (IV) 2 ethylhexoxide. In oneembodiment, the titanium compound comprises the alkoxide of a vicinal1,2-diol or polyol. In one embodiment, the 1,2-vicinal diol comprises afatty acid mono-ester of glycerol, often the fatty acid is oleic acid.

In one embodiment, the oil soluble titanium compound is a titaniumcarboxylate. In a further embodiment the titanium (IV) carboxylate istitanium neodecanoate.

The lubricating composition may in one embodiment further include aphosphorus-containing antiwear agent. Typically thephosphorus-containing antiwear agent may be a zincdialkyldithiophosphate, phosphite, phosphate, phosphonate, and ammoniumphosphate salts, or mixtures thereof. Zinc dialkyldithiophosphates areknown in the art. The antiwear agent, of whatever type, may be presentat 0 wt. % to 3 wt. %, or 0.1 wt. % to 1.5 wt. %, or 0.5 wt. % to 0.9wt. % of the lubricating composition.

Extreme Pressure (EP) agents may also be present. EP agents that aresoluble in the oil include sulfur- and chlorosulfur-containing EPagents, dimercaptothiadiazole or CS₂ derivatives of dispersants(typically succinimide dispersants), derivative of chlorinatedhydrocarbon EP agents and phosphorus EP agents. Examples of such EPagents include chlorinated wax; sulfurized olefins (such as sulfurizedisobutylene), a hydrocarbyl-substituted2,5-dimercapto-1,3,4-thiadiazole, or oligomers thereof, organic sulfidesand polysulfides such as dibenzyldisulfide, bis-(chlorobenzyl)disulfide, dibutyl tetrasulfide, sulfurized methyl ester of oleic acid,sulfurized alkylphenol, sulfurized dipentene, sulfurized terpene, andsulfurized Diels-Alder adducts; phosphosulfurized hydrocarbons such asthe reaction product of phosphorus sulfide with turpentine or methyloleate; phosphorus esters such as the dihydrocarbon and trihydrocarbonphosphites, e.g., dibutyl phosphite, diheptyl phosphite, dicyclohexylphosphite, pentylphenyl phosphite; dipentylphenyl phosphite, tridecylphosphite, distearyl phosphite and polypropylene substituted phenolphosphite; metal thiocarbamates such as zinc dioctyldithiocarbamate andbarium heptylphenol diacid; amine salts of alkyl and dialkylphosphoricacids or derivatives including, for example, the amine salt of areaction product of a dialkyldithiophosphoric acid with propylene oxideand subsequently followed by a further reaction with P₂O₅; and mixturesthereof (as described in U.S. Pat. No. 3,197,405). The amount of EPagent, if present, may be 0.001 to 5 wt. %, or 0.1 to 2 wt. %, or 0.2 to1 wt. %.

Foam inhibitors that may be useful in the lubricant compositions of thedisclosed technology include polysiloxanes, copolymers of ethyl acrylateand 2-ethylhexylacrylate and optionally vinyl acetate; demulsifiersincluding fluorinated polysiloxanes, trialkyl phosphates, polyethyleneglycols, polyethylene oxides, polypropylene oxides and (ethyleneoxide-propylene oxide) polymers. The amount of foam inhibitor, ifpresent, may be 0.001 to 0.012 wt. % or to 0.004 wt. %, or 0.001 to0.003 wt. %.

Viscosity improvers (also sometimes referred to as viscosity indeximprovers or viscosity modifiers) may be included in the compositions ofthis invention. Viscosity improvers are usually polymers, includingpolyisobutenes, polymethacrylates (PMA) and polymethacrylic acid esters,diene polymers, polyalkylstyrenes, esterified styrene-maleic anhydridecopolymers, hydrogenated alkenylarene-conjugated diene copolymers andpolyolefins also referred to as olefin copolymer or CP). PMA's areprepared from mixtures of methacrylate monomers having different alkylgroups. The alkyl groups may be either straight chain or branched chaingroups containing from 1 to 18 carbon atoms. Most PMA's are viscositymodifiers as well as pour point depressants. In certain embodiments, theviscosity index improver is a polyolefin comprising ethylene and one ormore higher olefin, such as propylene. Polymeric viscosity modifiers maybe present in a lubricating composition from 0.1 to 10 wt. %, 0.3 to 5wt. %, or 0.5 to 2.5 wt. %.

Pour point depressants that may be useful in the lubricant compositionsof the disclosed technology include polyalphaolefins, esters of maleicanhydride-styrene copolymers, poly(meth)acrylates, polyacrylates orpolyacrylamides. Pour point depressants may be present in a lubricatingcomposition from 0.1 to 10 wt. %, 0.3 to 5 wt. %, or 0.5 to 2.5 wt. %.

Demulsifiers include trialkyl phosphates, and various polymers andcopolymers of ethylene glycol, ethylene oxide, propylene oxide, ormixtures thereof.

Metal deactivators include derivatives of benzotriazoles (typicallytolyltriazole), 1,2,4-triazoles, benzimidazoles,2-alkyldithiobenzimidazoles or 2-alkyldithiobenzothiazoles. The metaldeactivators may also be described as corrosion inhibitors.

Seal swell agents include sulfolene derivatives Exxon Necton-37™ (FN1380) and Exxon Mineral Seal Oil™ (FN 3200).

Examples of suitable friction modifiers, other than the ash-freefriction modifiers disclosed above may include long chain fatty acidderivatives of amines, fatty esters, or fatty epoxides; fattyimidazolines such as condensation products of carboxylic acids andpolyalkylene-polyamines; amine salts of alkylphosphoric acids; fattyphosphonates; fatty phosphites; borated phospholipids, borated fattyepoxides; glycerol esters; borated glycerol esters; fatty amines;alkoxylated fatty amines; borated alkoxylated fatty amines; hydroxyl andpolyhydroxy fatty amines including tertiary hydroxy fatty amines;hydroxy alkyl amides; metal salts of fatty acids; metal salts of alkylsalicylates; fatty oxazolines; fatty ethoxylated alcohols; condensationproducts of carboxylic acids and polyalkylene polyamines; or reactionproducts from fatty carboxylic acids with guanidine, aminoguanidine,urea, or thiourea and salts thereof.

Friction modifiers may also encompass materials such as sulfurized fattycompounds and olefins, sunflower oil or soybean oil monoester of apolyol and an aliphatic carboxylic acid.

In another embodiment, the friction modifier may be a long chain fattyacid ester. In another embodiment, the long chain fatty acid ester maybe a mono-ester and in another embodiment the long chain fatty acidester may be a triglyceride.

The present technology discloses fully formulated lubricants as well asadditive concentrates for top-treating lubricants. Where the additiveconcentrate comprises the polyether compound, ash-free friction modifierand optional detergent, the present technology contemplates that anexisting lubricant may be top treated with 0.5 to 15 wt. % or 05 to 10wt. % or 0.5 to 5.0 wt. % or 0.5 to 3.0 wt. % or 0.5 to 1.5 wt. % or 0.5to 1.2 wt. % of the additive concentrate. By top treating the lubricant,the friction properties of the lubricant may be adjusted to render thetreated lubricant suitable for use in a scooter engine, even where thepre-treated lubricant was suitable for use in a motorcycle having anengine and a wet clutch. It will also be understood that one or more ofthe aforementioned “other performance additives” may be present in thefully formulated lubricant or may be present in the additiveconcentrate, provided the effective treat rate of the polyether compoundand ash-free friction modifier in the fully formulated lubricant doesnot fail to fall within the ranges taught herein.

A fully formulated lubricant composition in different embodiments mayhave a composition as disclosed in the following table:

Embodiments (wt. %) Additive A B C Polyether compound 0.025 to 4    0.05 to 1.8 0.1 to 0.8 Ash-free Friction Modifier 0.01 to 6   0.05 to4  0.1 to 2   Molybdenum Compound 0 to 2    0 to 1.2   0 to 0.6(Borated) Dispersant  0 to 12 0.5 to 8 1 to 6 Over-based Detergent 0 to9 0.5 to 8 1 to 5 Corrosion Inhibitor 0.05 to 2   0.1 to 1 0.2 to 0.5Dispersant Viscosity 0 to 5   0 to 4 0.05 to 2   Modifier Antioxidant0.1 to 13   0.1 to 10 0.5 to 5   Antiwear Agent 0.1 to 15   0.1 to 100.3 to 5   Viscosity Modifier  0 to 10 0.5 to 8 1 to 6 Any OtherPerformance  0 to 10   0 to 8 0 to 6 Additive Oil of Lubricating Majorportion typically balance to 100% Viscosity

An additive concentrate in different embodiments may have a compositionas disclosed in the following table:

Embodiments (wt. %) Additive A B C Polyether compound 5 to 80 15 to 5020 to 40 Ash-free Friction Modifier 5 to 50 10 to 40 15 to 30 Over-basedDetergent 0 to 90 10 to 75 30 to 70 Oil of Lubricating Viscosity Balanceto 100%; typically diluent oil in amount less than about 30%

INDUSTRIAL APPLICATION

The technology disclosed may include a method of lubricating one of awet clutch or an internal combustion engine, comprising supplying to thewet clutch or the engine a lubricating composition comprising (a) an oilof lubricating viscosity, (b) a polyether compound, (c) an over-baseddetergent, (d) an ash-free friction modifier; (e) a dispersant and (f)optionally, an antioxidant.

The technology disclosed may include a method of lubricating an internalcombustion engine comprising supplying to the engine a lubricatingcomposition as described above.

The internal combustion engine may be a 4-stroke engine. The internalcombustion engine may be fitted with an emission control system or aturbocharger. Examples of the emission control system includeparticulate filters, or systems employing selective catalytic reduction(SCR).

The internal combustion engine may be port fuel injected or directinjection. In one embodiment, the internal combustion engine is agasoline direct injection (GDI) engine.

The technology disclosed may include a method of lubricating a wetclutch, wherein the wet clutch comprises at least one clutch platehaving a non-ferrous surface and at least one clutch plate having aferrous surface, comprising supplying to the wet clutch, and moreparticularly, supplying between the interface of the ferrous andnon-ferrous surfaces, a lubricating composition as described herein.

The technology disclosed may include a method of reducing staticfriction between a ferrous and non-ferrous surface, such as may be foundin a wet clutch having at least one clutch plate having a non-ferroussurface and at least one clutch plate having a ferrous surface, themethod comprising supplying between the ferrous and non-ferrous clutchplate surfaces a lubricating composition as described herein.

It is contemplated that the lubricant compositions of the presentinvention may be employed in a wet clutch, that is, where clutch plateswhich are immersed in a lubricant. Such clutches are well known and notextensively described herein, save that they typically contain a two ormore plates. Plate materials may include steel (that is, a ferrousmaterial), and non-ferrous materials, such as paper, ceramic, and carbonfiber. The present technology is particularly useful in reducing staticfriction between a steel plate and a carbon fiber or fiberglass plate.While the present invention may be taught in relation to reducing atleast one of static friction and dynamic friction between a ferrous andnon-ferrous surface exemplified in a wet clutch, it will be understoodthat the compositions of the present invention may be useful in reducingone of static or dynamic friction between ferrous and non-ferroussurfaces in other contexts.

The lubricating compositions of the present invention may have a totalsulfated ash content of 1.2 wt. % or less. The sulfur content of thelubricating composition may be 1 wt. % or less, or 0.8 wt. % or less, or0.5 wt. % or less, or 0.3 wt. % or less. In one embodiment, the sulfurcontent may be in the range of 0.001 wt. % to 0.5 wt. %, or 0.01 wt. %to 0.3 wt. %. The phosphorus content may be 0.2 wt. % or less, or 0.12wt. % or less, or 0.1 wt. % or less, or 0.085 wt. % or less, or 0.08 wt.% or less, or even 0.06 wt. % or less, 0.055 wt. % or less, or 0.05 wt.% or less. In one embodiment, the phosphorus content may be 0.04 wt. %to 0.12 wt. %. In one embodiment, the phosphorus content may be 100 ppmto 1000 ppm, or 200 ppm to 600 ppm. The total sulfated ash content maybe 0.3 wt. % to 1.2 wt. %, or 0.5 wt. % to 1.1 wt. % of the lubricatingcomposition. In one embodiment, the sulfated ash content may be 0.5 wt.% to 1.1 wt. % of the lubricating composition.

In one embodiment, the lubricating composition may be characterized ashaving (i) a sulfur content of 0.5 wt. % or less, (ii) a phosphoruscontent of 0.15 wt. % or less, and (iii) a sulfated ash content of 0.5wt. % to 1.5 wt. % or less.

The lubricating composition may be characterized as having at least oneof (i) a sulfur content of 0.2 wt. % to 0.4 wt. % or less, (ii) aphosphorus content of 0.08 wt. % to 0.15 wt. %, and (iii) a sulfated ashcontent of 0.5 wt. % to 1.5 wt. % or less.

The lubricating composition may be characterized as having a sulfatedash content of 0.5 wt. % to 1.2 wt. %.

As used herein TBN values are (total base number) measured by themethodology described in D4739 (buffer).

The lubricating composition may be characterized as having a total basenumber (TBN) content of at least 5 mg KOH/g. The lubricating compositionmay be characterized as having a total base number (TBN) content of 6 to13 mg KOH/g, or 7 to 12 mg KOH/g. The lubricant may have a SAE viscositygrade of XW-Y, wherein X may be 0, 5, 10, or 15; and Y may be 16, 20,30, 40, or 50 or a monograde viscosity of SAE 20, 30, 40, or SAE 50.

The internal combustion engine disclosed herein may have a steel surfaceon a cylinder bore, cylinder block, or piston ring.

The internal combustion engine may have a surface of steel, or analuminum alloy, or an aluminum composite. The internal combustion enginemay be an aluminum block engine where the internal surface of thecylinder bores has been thermally coated with iron, such as by a plasmatransferred wire arc (PTWA) thermal spraying process. Thermally-coatediron surfaces may be subjected to conditioning to provide ultra-finesurfaces.

Examples

The following examples provide illustrations of the invention. Theseexamples are non-exhaustive and are not intended to limit the scope ofthe invention.

A series of 10W-30 motorcycle lubricants are prepared as summarized inTable 1. The inventive oil examples 1 and 2 of the invention contain apolyethyleneamine, an over-based detergent, an ash-free frictionmodifier, and a dispersant, as well as several other conventionallubricant additives. The inventive oils are evaluated and compared to asimilarly formulated oil without the polyetheramine (Comparative 1).

TABLE 1 Lubricating Compositions Comparative 1 Example 1 Example 2Mineral Oil Balance to Balance to Balance to 100% 100% 100% ViscosityModifier 0.625 0.625 0.625 PMA Pour Depressant 0.120 0.120 0.120 AminicAntioxidant 0.601 0.601 0.601 300 TBN Ca Sulfonate 0.087 0.087 0.087 400TBN Ca Sulfonate 0.518 0.518 0.518 255 TBN Ca Phenate 0.150 0.093 0.093Borated Succinimide Dispersant 0.100 0.100 0.100 Succinimide Dispersant1.532 1.532 1.532 Secondary ZDP 0.758 0.758 0.758 Sulfurized Olefin0.100 0.100 0.100 PDMS Anti-foam 0.010 0.010 0.010 Booster CompositionAminated polyether (PAG-24A) — 0.500 0.200 300 TBN Ca Sulfonate — —0.348 Oleyl Tartrimide — — 0.120 Total¹ 100.000 100.000 100.000 ¹Alltreat rates on an oil-free basis.

The lubricants are evaluated for balance of static and dynamic frictionperformance.

The industry-standard JASO T 903:2011 test utilizes a clutch packconsisting of several steel disks and fiber plates enclosed in a testhead. The clutch pack operates in a temperature controlled oil bath. Anelectric motor is then used to rotate the fiber plates to 3,600 RPMwhile the steel disks are held static in the test head. During thismotoring phase, there is no pressure applied to the clutch pack. Oncespeed and temperature set points are met, pressure is then applied tothe clutch pack to cause lock up. This event is referred to as a dynamicengagement. A metal disc connected to the electric motor simulatesvehicle inertia. During this dynamic engagement, parameters such asspeed and torque are measured and are used to calculate the DynamicFriction Characteristic Index (DFI) and Stop Time Index (STI). These arethe first two parameters which are used to classify an engine oil'sfrictional performance. The third parameter is called the StaticFriction Characteristic Index (SFI). For this evaluation, the same testrig is used, but now the evaluation begins with the pressure applied tothe clutch to facilitate lock up. A low speed (300 RPM), high torquemotor is used to ‘break’ the clutch pack loose and cause slippage. Onceagain, torque, speed, and other parameters are measured and used tocalculate SFI. For JASO T903:2011 MB specifications, SFI must fallbetween 0.5 and 1.25.

TABLE 2 Friction Measurements JASO T903:2011 Comparative 1 Example 1Example 2 Dynamic FI (DFI) 2.12 1.73 1.95 Static FI (SFI) 2.14 1.07 1.13Stop Time Index 2.11 1.77 1.94

As the results indicate, the inventive lubricant composition providesfor desired reduction in static friction.

It is known that some of the materials described above may interact inthe final formulation, so that the components of the final formulationmay be different from those that are initially added. The productsformed thereby, including the products formed upon employing lubricantcomposition of the present invention in its intended use, may not besusceptible of easy description. Nevertheless, all such modificationsand reaction products are included within the scope of the presentinvention; the present invention encompasses lubricant compositionprepared by admixing the components described above.

As used herein, the term “hydrocarbyl substituent” or “hydrocarbylgroup” is used in its ordinary sense, which is well-known to thoseskilled in the art. Specifically, it refers to a group having a carbonatom directly attached to the remainder of the molecule and havingpredominantly hydrocarbon character. Examples of hydrocarbyl groupsinclude:

(i) hydrocarbon substituents, that is, aliphatic (e.g., alkyl oralkenyl), alicyclic (e.g., cycloalkyl, cycloalkenyl) substituents, andaromatic-, aliphatic-, and alicyclic-substituted aromatic substituents,as well as cyclic substituents wherein the ring is completed throughanother portion of the molecule (e.g., two substituents together form aring);

(ii) substituted hydrocarbon substituents, that is, substituentscontaining non-hydrocarbon groups which, in the context of thisinvention, do not alter the predominantly hydrocarbon nature of thesubstituent (e.g., halo (especially chloro and fluoro), hydroxy, alkoxy,mercapto, alkylmercapto, nitro, nitroso, and sulphoxy);

(iii) hetero substituents, that is, substituents which, while having apredominantly hydrocarbon character, in the context of this invention,contain other than carbon in a ring or chain otherwise composed ofcarbon atoms; and

(iv) heteroatoms include sulphur, oxygen, nitrogen, and encompasssubstituents as pyridyl, furyl, thienyl and imidazolyl. In general, nomore than two, preferably no more than one, non-hydrocarbon substituentwill be present for every ten carbon atoms in the hydrocarbyl group;typically, there will be no non-hydrocarbon substituents in thehydrocarbyl group.

Each of the documents referred to above is incorporated herein byreference. Except in the examples, or where otherwise explicitlyindicated, all numerical quantities in this description specifyingamounts of materials, reaction conditions, molecular weights, number ofcarbon atoms, and the like, are to be understood as modified by the word“about.” Unless otherwise indicated, each chemical or compositionreferred to herein should be interpreted as being a commercial gradematerial which may contain the isomers, by-products, derivatives, andother such materials which are normally understood to be present in thecommercial grade. However, the amount of each chemical component ispresented exclusive of any solvent or diluent oil, which may becustomarily present in the commercial material, unless otherwiseindicated. It is to be understood that the upper and lower amount,range, and ratio limits set forth herein may be independently combined.Similarly, the ranges and amounts for each element of the invention maybe used together with ranges or amounts for any of the other elements.

As used herein the term “free of” defines the absence of a material andthe term “substantially free of” defines an amount which is present asimpurities, e.g., a trace amount or a non-effective amount.

While the invention has been explained in relation to its preferredembodiments, it is to be understood that various modifications thereofwill become apparent to those skilled in the art upon reading thespecification. Therefore, it is to be understood that the inventiondisclosed herein is intended to cover such modifications as fall withinthe scope of the appended claims.

What is claimed is:
 1. A lubricant composition comprising: a) an oil oflubricating viscosity, b) a polyether compound, c) an over-baseddetergent, d) a dispersant, e) optimally, an ash-free friction modifier,and f) optionally, an antioxidant, wherein the polyether is representedby the formula:RO[CH₂CH(R¹)O]_(n)A where R is a hydrogen or hydrocarbyl group of 1 to32 carbon atoms, R¹ is selected from the group consisting of hydrogen,hydrocarbyl groups of 1 to 6 carbon atoms, and mixtures thereof, n is anumber from 2 to about 50, and A is selected from the group consistingof hydrogen, R¹, —R⁷NR²R², C═OR⁸ and —NR³R³, where each R² isindependently hydrogen or a hydrocarbyl group of 1 to 24 carbon atoms,each R³ is independently hydrogen, a hydrocarbyl group of 1 to 24 carbonatoms, or —[R⁴N(R⁵)]_(p)R⁶ where R⁴ is C₂-C₁₀ alkylene, R⁵ and R⁶ areindependently hydrogen or a hydrocarbyl group of 1 to 6, R⁷ and R⁸ areindependently hydrogen or a hydrocarbyl group of 1 to 6 carbon atoms,and p is a number from 1-7.
 2. (canceled)
 3. The lubricating compositionof claim 1, wherein the polyether compound is a polyetheraminerepresented by the formula RO[CH₂CH(R¹)O]_(n)A, wherein: R is ahydrocarbyl group of 2 to 26 carbon atoms, A is —R⁷NR²R², each R² isindependently hydrogen or a hydrocarbyl group of 1 to 24, R⁷ is ahydrocarbyl group of 2 to 4 carbon atoms, and n is 12 to
 36. 4. Thelubricating composition of claim 1, comprising the ash-free frictionmodifier and wherein the ash-free friction modifier is derived from analpha-hydroxy carboxylic acid.
 5. (canceled)
 6. The lubricatingcomposition of claim 1, wherein the ash-free friction modifier ispresent and is an imide, ester, or amide of tartaric acid.
 7. (canceled)8. The lubricating composition of claim 1, wherein the over-baseddetergent comprises a metal containing detergent and wherein the metalis selected from the group consisting of sodium, magnesium and calcium.9. (canceled)
 10. The lubricating composition of claim 1, wherein theover-based detergent is selected from the group consisting ofsulfonates, phenates, salicylates, salixarates and mixtures thereof. 11.The lubricating composition of claim 1, wherein the over-based detergentis substantially free of phenates.
 12. The lubricating composition ofclaim 1, wherein the over-based detergent comprises a calcium sulfonatedetergent.
 13. The lubricating composition of claim 1, wherein thedispersant is a succinimide dispersant.
 14. The lubricating compositionof claim 1, wherein the dispersant comprises a borated dispersant. 15.(canceled)
 16. The lubricating composition of claim 1, furthercomprising a molybdenum containing compound.
 17. The lubricatingcomposition of claim 1, wherein the composition is substantially free ofa molybdenum containing compound.
 18. The lubricating composition ofclaim 1, wherein the composition is substantially free of phenoliccompounds.
 19. The lubricating composition of claim 1, wherein thecomposition comprises: a) a major amount of an oil of lubricatingviscosity, b) 0.05 to 3.0 wt. % of the polyether compound, c) 0.05 to3.0 wt. % of the over-based detergent, d) 0.05 to 2.0 wt. % of theash-free friction modifier, and e) 0.1 to 12 wt. % of the dispersant.20. A method of lubricating a wet clutch comprising, supplying to thewet clutch a lubricating composition of claim
 1. 21. The method of claim20, wherein the wet clutch comprises at least one clutch plate having anon-ferrous surface and at least one clutch plate having a ferroussurface.
 22. A method of reducing static friction between a ferrous andnon-ferrous surface in a wet clutch, wherein the wet clutch comprises atleast one clutch plate having a non-ferrous surface and at least oneclutch plate having a ferrous surface, the method comprising supplyingbetween the ferrous and non-ferrous clutch plate surfaces a lubricatingcomposition of claim
 1. 23. A method of lubricating an engine comprisingsupplying to engine a lubricating composition of claim
 1. 24. The methodof claim 23, wherein the engine a 4-stroke engine.
 25. The method ofclaim 23, wherein the engine is an air-cooled engine.
 26. The method ofclaim 23, wherein the lubricating composition does not lubricate a wetclutch.
 27. (canceled)
 28. (canceled)
 29. (canceled)
 30. (canceled) 31.(canceled)
 32. (canceled)
 33. (canceled)